Reducing Rendering Time: Video Editing
TL;DR:  No, because the Blender VSE is single-threaded.

I haven't done a code dive, but what it looks like Blender is doing is serially feeding each frame through its respective pipeline then into the encoder.  That means the only time Blender will multithread or use GPU when rendering video is if a specific frame uses a pipeline that multithreads.

You'll find this is also true of proxy generation.  Rebuilding proxies in Blender will always single thread.

For my workflow, I've gotten around this bottleneck by making use of a chunking and stitching method similar to bpsrender.